1. Field of the Invention
Embodiments of the present invention generally relate to a method and apparatus for transcoding audio data.
2. Description of the Related Art
The progress in audio coding algorithms and the widespread of digital media distribution pushed the efforts to standardize formats for audio distribution. Many audio standards in the last two decades have been proposed and successfully deployed in different applications platforms. Among these noticeable standards are the MPEG-1 audio standard for audio file storage, MPEG-2 and MPEG-4 audio standards for broadcasting and networking, and the Dolby standards for TV broadcasting.
In many application scenarios, transcoding between two different audio standards is needed. For example, satellite broadcasting in the united states uses MPEG-2 audio standards at 256 kbps, and the DVD recoding uses Dolby digital standard for audio storage at a similar bitrate. The straightforward audio transcoder uses a tandem realization of an audio decoder for the first system followed by an audio encoder for the second system. Typically the two components in the tandem realization are completely independent. However, most audio standards use subband coding schemes with similar architecture. Therefore, the decoder information can be exploited to reduce the complexity of the audio encoder.
Therefore, there is a need for a method and/or apparatus for improving the transcoding of audio data.